Safety elevator interlock



July 17, 1923.

F. M. COFFIN SAFETY ELEVATOR INTERLOCK Filed April 23, 1921 nvemboz @515, GMW @fw Patented July i7, 1923,

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reen-a M. corran, or PELHAM, New YORK.

SAFETY ELEVATOR- INTE'RLOCK.

Application filed April -23, 1921. Serial No. 463,746.

To all 'whom t may' conce/m.'

-Be it'known that I, FRANK M. Corsini,

a citizen `of the United States, residing et Pelham, New York, have invented new and useful Improvements in Safety Elevator lnterlocks, of which the following is specifiproved device which is, automatically operative to prevent opening of the `doors while the elevator is in motionand which may be applied to elevator'systeins having any form of car operating tnieans.r

A further object of the invention .is the provision of a device of the character set forth by 'means of which, when the car .is at rest in the proper Vposition in front of the landing, the door` may be openedweither from the landing or from within the car.'

v A further object of the invent-ionis* to provide a device vof the character set forth in which a plurality of selector switches are employed for releasingtlie door locking means, and 'which switches are preferably operated by the car itself. whereby-the doors cannot be opened untilk thefcar is at rest opposite thedoor opening.

With the vforegoing Aand other object-s 'in view, which will appear as the description proceeds, the-invention consists in the novel features of construction and coinbination of parts which will be more fully described hereinafter and particularly pointed yout in the claims. f'

The drawing accompanying and form-ing part of thisspecificaftion is a diagrammatic side elevation of a preferred'embodiment of the invention applied vto an electrically operated elevator.v V

Referringto thel drawing,A 2 `designates,

the Wall of lan elevator shaft, which is illustiafted asyhaving four land-ings, 3, 4t, 5 and 6 respectively. Each lofl the fourlanding doors (not shown) is equipped witha suitable electro-inechan-ical lock. As the lock itself, however', forins'no part of the present invention, l have,` for the sake of clearness', oinitted thedetai-ls thereof and have illustrated only an electro-magnetic coil T for each door lock.

In the form of the device illustratedherein, each of vthe coils 7 is adapted to be electrically connected b v means of wires 8' Iand 9 with main line conductors lO'and 1i `illustrated in the drawing,

respectively, leading to a source of electrical energy, said conductors being alsoconnected with the terminals of a. motor M which mayating the carv` kin anyA wellbe yused for oper known manner. n

`On the elevator control board (not shown), the conductor l1k and wire 9 run parallel, andare each separated to 'forni a gap, a bridging contact beingprovide'd .for closing the circuit ,acrossv said gaps.

Thisbridging contact comprises an electroinavgnet having a corel Aprovided at each end lthereof with a bridge piece 16 and 17, adapted to` bridge the gaps in the conductor ll and wire 9 respectively. For energizing the core, a coil l2 is provided having lcad'f wires 13 and 14 by which the coilinay be connected to the niain yline conductors,A or

to any Iother suitable/source ofenergy, sucli for instanceas a battery. l The wires 13 and 14 will include in theirl circuit any suit-able form of elevator operating and controlling switch, suchL for instance as theswitch 09 vwhich may vbe-located'either in :the car it selfor one of such switches locatedrat each landing and adapted to be operated :i-

pusli-button, in the usual'injannen. -Tbese devices are all well-known inthe fart, and therefore it is deemedy unnecessaryto describe them in detail.

. lltou'nted in the elevator shaft orhatchJ way, vopposite each of the doors, isan electric switch r`18 adapted tov norinallyinaintain the circuit to the coils open, as shown at theupperniost and the two loweiflandings. n either byrsprings (not showiillor by ymeans `Vlof gravity, and are each providedv'itli a roller 19 adapted to contactwith afcain 20 of any suitable inaterial andy form,` carried bythe car 21, showny in dotted lines, f-

for operating the switches into circuit` closing position, as shown at thefthirdilanding as soonas the 'car has arrived at its front of thel landing. i y

The operation of the devicewill loe-obvious from the foregoing description taken in connection with the f drawing.` The switches 18 arefnormally retained in Icircuitpioper position in These switches Ymay v,be held open breaking position, and the doors iat the .va-1.

rious landings locked. lf^issuming the car to be at rest the ycore of the electroinagnetA will have. fallen r by :gravity softhat its bridge piece 17 contacts with the'terminals of the wire 9, whereby the bridge piece "16 is moved away from the terminals of the conductor 11 so that the motor is inoperative. If it is desired to operate the car, the usual lever within the car, or a push button at one of the landings, is operated to throw the car-operating switch 22 into circuit-closing position, which closes the circuit through the coil of the electromagnet A and thus energizes the core 15, which moves upward until its bridge piece 16 contacts with the terminals of the conductor 11, thus opening the circuit to the coils and closing 'the circuit to the motor, whereby the car will be raised or lowered to the desired landing. On its arrival there,v the cam 2O will have thrown the switch 18 at that landing` into circuit closing` position, but owing to the fact that the circuit is brokeny by the removalof the bridge piece 17 from contact with the terminals of the wire 9, no current can pass through the coil 7 until the switch 22 has been opened to open the circuit to the motor. When the lever or push buttonhas been operated into circuitbreaking position, current will cease to pass through the coil of the electromagnet A, which vthus becomes deenergized and the coreJ 15 falls by gravity until its bridge piece 17 again contacts with the terminals of the wire 9, while the bridge piece 16 has moved away from the terminals of the conductor 11 and thus broken the circuit through the motor so that the car stops. It will he obvious that with the bridging piece 17 in contact with the terminals of the wire 9 the circuit will be closed to the coil 7 at the particular landing where the car has stopped` whereby the core of the solenoid, or the keeper of the electromagnet at that landing will be energized thereby to withdraw the lock from the door and permit the same to be opened either from the landing or from within the car. It will thus be obvious that, although the switches 18 are successively operated every time the car travels up or down the shaft, it will be impossible for the doors to be opened while the car is moving and therefore rthe moment the car starts to move from rest the door which has been unlocked automatically becomes locked, because the circuit through the coils 7 is open4 as long as the electromagnet A is energized, and when said magnet is deenergized, the circuit through the motor is opened by reason of the falling of the bridge piece 16 from the terminals of the conductor 11. f

Whilel have for purposes of illustration shown my safety device in connection with an electrically operated elevator, I desire it `distinctly understood that my invention is not`limited to such application, as I am well aware that the device is capable of other applications and that many mechanical changes and modifications may be made in operable t0 the details of construction without departing from the spirit and scope of the invention as set forth in the claims appended hereto.

Having thus described my invention, what I claim is:

1. rThe combination with an elevator having doors normally retained in locked position and means for actuating the elevator,0f electrically operated means for unlocking said doors, and an electromagnet having a circuit-closing member in the circuit 0f said unlocking means, said electromagnet being adapted to be energized when the elevatoractuating means is operated, thereby to open said circuit. n i

2. The combination with an elevator havingdoors normally retained in locked position and means for actuating said elevator, of electrically operated means for unlocking said doors, an electromagnet having a pair of circuit-closing elements one effective to close a circuit through said elevator-actuating means and the other to close a circuit through said unlocking means, and means for energizing said electromagnet thereby to open one circuit and close the other.

3. The combination with an elevator having doors normally retained in lockedposition and means for operating the elevator, of an electromagnet associated with each of said doors for withdrawing the locks therefrom, said electromagnets being electrically connected with a source of energy, a circuit closing device in the circuit of each of said electromagnets and operable to close said circuit during movement of the elevator, and a second circ-uit controlling device in said circuit automatically operative to retain the' circuit open while the elevator is moving.

4:. The combination with an elevator having doors normally retained in locked position and means for operating the elevator, of an electromagnetically operated member associated with each of said doors for withdrawing the locks therefrom, said electromagnetically operated members being connected with. a source of electrical energy, a

circuit-controlling device in the circuit ofl each of said members and operable by the passageof thee-ar to close said circuit, and a second circuit-controlling device in said circuit and automatically operative upon actuation of said elevator-operating means to open said circuit.

5. The combination with an elevator havf ing doors normally retained in locked position and means `for operating the elevator, of

n an electromagnet adjacent to each of said doors for unlocking the same, said electromagnets being electrically connected with a source of energy, a circuit-controlling device in the circuit of each of said members and close said circuit during movement of the elevator, an electromagnet having a pair of circuit-closing elements one effective to Close a ciroult through said elevator-operating means and the other to close f the circuit through said circuit-controlling devices7 said oirouiis-closingy elements being' so disposed that one is in cirouit-c1osng position and the other in circuit-breaking position when the electromagnet is energized and vice versa AWhen the electromagnet is deenergized, and means for closing a circuit through the coil of said eleotromagnet thereby to energize the same.

In testimony whereof have signed my name to this specification.

FRANKM. ooFFIN. 

